radio particle emission rate corresponds with mic input volume

Assets/_PROJECT/Prefabs/ModelGeneration/Radio.prefab

@@ -1074,7 +1074,7 @@ ParticleSystem:
     rateOverTime:
       serializedVersion: 2
       minMaxState: 0
-      scalar: 50
+      scalar: 3
       minScalar: 10
       maxCurve:
         serializedVersion: 2
@@ -5310,6 +5310,8 @@ MonoBehaviour:
   radioButton: {fileID: 1588960997487099811}
   computerScreen: {fileID: 0}
   particles: {fileID: 4781044067799935830}
+  minimumEmissionRate: 3
+  maximumEmissionRate: 50
 --- !u!114 &198665210576292642
 MonoBehaviour:
   m_ObjectHideFlags: 0

Assets/_PROJECT/Scripts/ModeGeneration/FMODWhisperBridge.cs

@@ -64,6 +64,11 @@ public class FMODWhisperBridge : MonoBehaviour
     private bool isRecordingActivated = false;
     private bool _skipOneFeedFrame = false;
 
+    // --- Speech Volume Measurement ---
+    private float currentVolumeRms = 0f;      // Smoothed RMS for external access
+    private float volumeSmoothing = 0.15f;    // How fast the meter reacts (0.1–0.3 good)
+
+
     private void Awake()
     {
         if (!whisper) whisper = FindObjectOfType<WhisperManager>();
@@ -254,6 +259,29 @@ public class FMODWhisperBridge : MonoBehaviour
         Debug.Log("[FMOD→Whisper] Stream deactivated (Whisper stopped; FMOD still recording).");
     }
 
+    /// <summary>
+    /// Returns current microphone level in dBFS (decibels relative to full-scale).
+    /// 0 dBFS = digital clipping; normal speech is typically around -35 to -20 dBFS.
+    /// </summary>
+    public float GetCurrentVolumeDb()
+    {
+        // Guard from log(0)
+        const float minRms = 1e-7f;
+        float rms = Mathf.Clamp(currentVolumeRms, minRms, 1f);
+        return 20f * Mathf.Log10(rms);
+    }
+
+    /// <summary>
+    /// Returns a UI-friendly 0..1 loudness from the current dBFS value.
+    /// Adjust the dB range to your content/environment if needed.
+    /// </summary>
+    public float GetNormalizedVolume01()
+    {
+        float db = GetCurrentVolumeDb();          // typically ~ -60 .. -15 during use
+        return Mathf.Clamp01(Mathf.InverseLerp(-60f, -15f, db));
+    }
+
+
     private void Update()
     {
         // Always tick FMOD
@@ -295,11 +323,35 @@ public class FMODWhisperBridge : MonoBehaviour
 
         try
         {
+
+            float rmsAccumulator = 0f;
+            int rmsSampleCount = 0;
+
+            // 1) Measure volume
+            if (len1 > 0)
+            {
+                ComputeRmsFromPcm16(p1, len1, ref rmsAccumulator, ref rmsSampleCount);
+            }
+            if (len2 > 0)
+            {
+                ComputeRmsFromPcm16(p2, len2, ref rmsAccumulator, ref rmsSampleCount);
+            }
+
+            if (rmsSampleCount > 0)
+            {
+                float rms = Mathf.Sqrt(rmsAccumulator / rmsSampleCount);
+
+                // Smooth the value
+                currentVolumeRms = Mathf.Lerp(currentVolumeRms, rms, 1f - Mathf.Pow(1f - volumeSmoothing, Time.deltaTime * 60f));
+            }
+
+            // 2) Feed audio to Whisper ONLY when active
             if (shouldFeed && !_skipOneFeedFrame)
             {
                 if (len1 > 0) CopyPcm16ToFloatAndFeed(p1, len1);
                 if (len2 > 0) CopyPcm16ToFloatAndFeed(p2, len2);
             }
+
             // If skipping, we just discard this frame to ensure no stale data leaks.
         }
         finally
@@ -427,4 +479,30 @@ public class FMODWhisperBridge : MonoBehaviour
         }
     }
 
+    /// <summary>
+    /// Computes RMS (root mean square) from a PCM16 block using only safe code.
+    /// Uses the shared _shortOverlay buffer (no allocations).
+    /// Accumulates results into accumulator + sampleCount.
+    /// </summary>
+    private void ComputeRmsFromPcm16(IntPtr src, uint byteLen, ref float accumulator, ref int sampleCount)
+    {
+        // Number of PCM16 samples (2 bytes per sample)
+        int samples = (int)(byteLen / 2);
+        if (samples <= 0) return;
+
+        // Ensure overlay buffer exists & is large enough
+        EnsureShortOverlay(samples, out short[] sBuf);
+
+        // Copy PCM16 into managed buffer (safe)
+        Marshal.Copy(src, sBuf, 0, samples);
+
+        // Accumulate squared amplitude
+        for (int i = 0; i < samples; i++)
+        {
+            float v = sBuf[i] / 32768f;   // normalize to [-1..1]
+            accumulator += v * v;
+        }
+
+        sampleCount += samples;
+    }
 }

Assets/_PROJECT/Scripts/ModeGeneration/ShapeDetection/RadioTransmitter.cs

@@ -14,9 +14,14 @@ public class RadioTransmitter : XRGrabInteractable
     public FMODWhisperBridge fmodWhisperBridge;
     public ReleasableButton radioButton;
     public TextMeshProUGUI computerScreen;
+
+    [Header("Particle System Config")]
     public ParticleSystem particles;
+    public float baseEmissionRate = 3;
+    public float maxExtraEmissionRate = 50;
 
     private bool isProcessing;
+    private ParticleSystem.EmissionModule particleEmission;
 
     // Start is called before the first frame update
     void Start()
@@ -26,14 +31,20 @@ public class RadioTransmitter : XRGrabInteractable
         radioButton.Lock();
         isProcessing = false;
 
-        var emission = particles.emission;
+        particleEmission = particles.emission;
-        emission.enabled = false;
+        particleEmission.enabled = false;
     }
 
     // Update is called once per frame
     void Update()
     {
-        particles.transform.LookAt(computerScreen.transform.position);
+        if (particles.emission.enabled)
+        {
+            particles.transform.LookAt(computerScreen.transform.position);
+            Debug.Log("speech volume normalized: " + fmodWhisperBridge.GetNormalizedVolume01());
+            Debug.Log("speech volume decibels: " + fmodWhisperBridge.GetCurrentVolumeDb());
+            particleEmission.rateOverTime = baseEmissionRate + fmodWhisperBridge.GetNormalizedVolume01() * maxExtraEmissionRate;
+        }
     }
 
     protected async override void OnSelectEntered(SelectEnterEventArgs args)
@@ -55,8 +66,7 @@ public class RadioTransmitter : XRGrabInteractable
             fmodWhisperBridge.OnWhisperSegmentFinished += OnPlayerSpeechFinished;
             fmodWhisperBridge.ActivateRecording();
 
-            var emission = particles.emission;
+            particleEmission.enabled = true;
-            emission.enabled = true;
         }
     }
 
@@ -81,7 +91,6 @@ public class RadioTransmitter : XRGrabInteractable
         fmodWhisperBridge.OnWhisperSegmentFinished -= OnPlayerSpeechFinished;
         fmodWhisperBridge.DeactivateRecording();
 
-        var emission = particles.emission;
+        particleEmission.enabled = false;
-        emission.enabled = false;
     }
 }